Jim Parsons and Kaley Cuoco
Actors Jim Parsons and Kaley Cuoco at The Paley Center For Media's 33rd Annual PALEYFEST Getty

Sheldon will remain Sheldon! It looks like Big Bang Theory star Jim Parsons couldn't resist a funny banter when Penny aka Kaley Cuoco shared a little tease in the form of a shirtless snap on her Instagram account.

"Atomic Blonde", the CBS actress wrote alongside the sexy snap that offered a subtle flash of skin as Cuoco posed in a jacket and black lingerie minus any top.

Interestingly enough, the cheeky picture drew several admirers – one of them being none other than the 31-year-old actress' TBBT co-star Parsons. Known for his hilarious repartee with Cuoco's character (Penny) on the popular sitcom, Parsons continued with his witty exchange on the social media photo as well.

Responding to Cuoco's skin show in the image, the Sheldon actor poked fun, writing, "Where is your shirt, missy?!?" Not the one to ignore, even the actress shot back, writing "LOL" in all capital letters for her co-star's silly comment.

And while Penny might be ready to let go, Big Bang Theory loyalists unfailingly teased Parsons for his hilarious dig on Instagram.

"@therealjimparsons I'm sure that was the Sheldon in you lol," one fan commented addressing the famous wordplay between Sheldon and Penny on the show.

"That comment by Jim is reminiscent of Series 7 Episode 11. Mind you Jim, let the lady relax in any way she wishes. Great show and looking forward to Series 11," shared another Instagram user.

Amid the flurry of witty fan reactions, however, most seemed to side with Cuoco, giving Sheldon a piece of their mind. "@therealjimparsons the woman has the right to pick her own clothes. I believe in equality in all," someone wrote.

Another fan tagged both the actors in a raving comment that read, "you're too cute."

Apart from their social media exchanges, Parsons and Cuoco are both currently busy on season 11 of their hit CBS show. Most recently, the actress shared an on-set pic, confirming that production has begun on the upcoming season of The Big Bang Theory.

"We're baaaaaacccckkkkk!" Cuoco captioned the back-to-set pic.